First Look: V-Moda Vamp Headphone Amp + Battery Pack for iPhone 4/4S

"Snake oil" isn't a phrase we use a lot around here, but when it comes up, it tends to be for one of two types of accessories -- cheap little add-ons that do little to enhance the user experience, or absurdly expensive ones that offer little practical benefit. Most headphone port alternatives we've seen fall into the former category, but V-Moda's Vamp ($650) clearly isn't cheap: this rubber, plastic, and metal case is an iPhone 4/4S-only headphone amplifier and battery pack, rebranded and tweaked from Japanese developer VentureCraft's previously released GO-DAP 4.0. Vamp is pitched as a "pure sound" alternative to using the iPhone's built-in headphone port, running digital* output from the Dock Connector port through the accessory's own audio processor, amplifiers, and 3.5mm audio-out port. The vast majority of users and headphones will derive little to no benefit from this post-processing, but owners of particularly inefficient headphones may find that Vamp increases their volume or otherwise changes the way they sound. In our tests with two relatively inefficient headphones, the difference between using Vamp or the iPhone 4S's headphone port was little more than a volume boost, with no discernible improvement in audio quality. Given the staggering price tag, it's also disappointing that Vamp uses a confusingly backwards user interface, requiring an instructional insert just to explain the three-position power switch on top, with additional explanations for the oddly recessed gain and reset switches on the bottom. Another button toggles between "pure" and "VQ" audio modes, the latter somewhat ironically equalized by V-Moda, which also boosted the battery pack inside to 2200mAh, tweaked the amplifiers inside, and added a logo to the back. Though we've liked a lot of V-Moda's impressively-designed headphones in the past, this rebadged accessory strikes us as an extremely poor investment, both due to the limited value of the functionality it offers and the fact that it's specific to soon-to-be-outdated iPhone models -- moreover, ones that have rarely been criticized for poor sound quality. We won't be giving it a full review, as we can't imagine who would need more detailed buying advice for something so expensive and underwhelming. [Editor's Note: The term "line-level" was replaced with "digital" on June 16, 2012 after publication of this First Look.]

Editors' Note: iLounge only reviews products in "final" form, but many companies now change their offerings - sometimes several times - after our reviews have been published.
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